[andrewT]

I've got a 488 filled to under freeze plugs (no crud in system was all cleaned out and have already drained coolant clean a few times)
11:1 kauffman d ports with a torker 2
New cardone water pump with divider plate
Champion 3 core radiator with volvo electric fans that pull a ton of air
Running vr1 racing oil
Timing is not retarded at all and heater core is not connected

Weather here in Canada right now is like a cool new York summer day. Breezy and not humid at all
Car is getting up to 200 water real fast. The fans have a switch installed to come on at 180 (switch is on the rad itself). Seems the fans don't kick on until my gauge reads about 220 and then drops only a little 'til they cut out at about 200. Temps keep yo-yoing. Oil temps hover at 200 then climb up to 240..this is after a 20 minute drive in low traffic stop and go driving. I put the electric fans because I was having the same issue with my factory fan setup. Driving and getting airflow vs dead stop idling doesn't seem to help lower temps. I know synthetic oil will help with the oil temps but the water is definitely nerve wracking here.

With an IR thermometer I read about 30 degrees cooler at the rad than at the thermostat. Temp sensor is on the crossover at the front of the intake. The car does not boil over. The coolant is 50/50 mix.. I've tried a 180 thermostat with a small by pass hole and a 195 with just a dimple and both do the same.

I'm out of ideas. The only thing I'm wondering is since my torker 2 has no water flow at the back of the heads (they're just plugged) is if sending the water from the back of the heads to the front of the intake will help with cooling somehow.

I'm going to put some pictures up if I can figure out how.. You guys with filled blocks that aren't having these issues baffle me!

Please help

[andrewT]

Here are some pictures.
Also transmission has a separate cooler.

I'm really wondering if bringin water from the back of heads to the front somehow will help with circulation and fix my issues
Thanks all!

[chrisp]

What type of impeller is on the pump & did you clearance the divider plate ?

[andrewT]

Originally Posted by chrisp

What type of impeller is on the pump & did you clearance the divider plate ?

I honestly can't remember. This has been a slow project. I did not clearance the plate though
Excuse my ignorance but could that alone be causing heat rise as high and quick as this?

[Formulajones]

You said your temp sensor for the fans is on the radiator correct?

It's not one of those probes you stick in the fins is it? We just experimented with one of those controllers. While the adjustable rheostat is nice, we found using the radiator as a heat source for the switch was very inconsistent and wouldn't kick the fans on until the engine was pretty darn hot. It got to a point we turned the rheostat nearly all the way down but then it would kick the fans on and never shut down. I theorized I think it has to do with the ambient air flow coming across the radiator combined with hot under hood temps causing that temp probe to do wonky things. When we were moving down the road the fans wouldn't even work at all as the engine temp creeped. Too much cool outside air moving through keeping the probe cold.

Once we switched it over to a switch that screwed to the engine and controlled the fans that way, suddenly they worked as intended, turned on and off at the temps we wanted and now keeps the engine cooled properly.

Just based on that experience, I'll never use a controller again that relies on the radiator temps to control the fans. Much more accurate to use a temp sender in the head or intake manifold. Something to think about and easy/cheap to try.

[JUDGE3]

my well known engine builder filled my block same as yours and it overheated everytime for awhile really had me worried. he said to "burp" the system repeatedly at hose connections (carefully of course) and it finally went away completely and ran nice and cool at 175. apparently sometimes block fill can trap air in spots.

[andrewT]

Originally Posted by Formulajones

You said your temp sensor for the fans is on the radiator correct?

It's not one of those probes you stick in the fins is it? We just experimented with one of those controllers. While the adjustable rheostat is nice, we found using the radiator as a heat source for the switch was very inconsistent and wouldn't kick the fans on until the engine was pretty darn hot. It got to a point we turned the rheostat nearly all the way down but then it would kick the fans on and never shut down. I theorized I think it has to do with the ambient air flow coming across the radiator combined with hot under hood temps causing that temp probe to do wonky things. When we were moving down the road the fans wouldn't even work at all as the engine temp creeped. Too much cool outside air moving through keeping the probe cold.

Once we switched it over to a switch that screwed to the engine and controlled the fans that way, suddenly they worked as intended, turned on and off at the temps we wanted and now keeps the engine cooled properly.

Just based on that experience, I'll never use a controller again that relies on the radiator temps to control the fans. Much more accurate to use a temp sender in the head or intake manifold. Something to think about and easy/cheap to try.

This literally sounds exactly like what I'm having an issue with
Do you know what brand probe you put on the intake/engine

The only ones I could find that fit the teeny thread of my rad was a cheap offshore one that I don't trust much anyway

[Formulajones]

The one we used in the engine are just the simple pipe thread temp senders that are all over ebay, and cost ~$20 We actually bought 3 of them with different temp ratings to experiment with. Just pick one with a fan on/off rating your happy with. They aren't exact and seem to vary 5 degrees or so but not a big deal.

For what it's worth, they came from different suppliers, one is a different name brand, but they all look identical holding them in your hand. So I suspect they are made at the same place.

[chrisp]

Originally Posted by andrewT

I honestly can't remember. This has been a slow project. I did not clearance the plate though
Excuse my ignorance but could that alone be causing heat rise as high and quick as this?

Could be , when the T-stat is open are you seeing a good flow through the rad when cap is off ?

[JSPONT]

I dropped 15 degrees no other change when I clearance the pump

[Cliff R]

"What type of impeller is on the pump & did you clearance the divider plate ?"

+2

Remove the water pump and see if it has a stamped steel impeller on it. If so get one with a cast impeller instead. That will typically knock 20-30 degrees running temps right out of one of these engines.......Cliff

[steve25]

What do the plugs look like?

I don't care about the stateded 11 to 1 the motor has, what is the cranking compression checking in at?

Has TDC been doubled checked?

What Carb is on the motor, and had this been run before on a motor close to this ones Cid and a motor that was Camed close?

[adynes]

Originally Posted by andrewT

Here are some pictures.
Also transmission has a separate cooler.

I'm really wondering if bringin water from the back of heads to the front somehow will help with circulation and fix my issues
Thanks all!

I've noticed that my factory gage isn't very accurate compared to the reading from my efi computer.

Also, in your third picture, is that your sensor mounted in the top of the passenger side ("cold side") tank of the radiator? If so, I think you need to mount it on the other side, the hot side of the radiator (or on the engine itself). Aside from being the wrong side of the radiator temperature-wise, the sensor located there might not even be submerged in coolant, as the coolant level gets pulled down significantly on the suction side. My coolant sensor for the efi (that controls the electric fans) is in the crossover.

[02Hawk]

I would borrow another guage and see if that is the problem....don't ask me why I have tried this

[02Hawk]

How big is that WP pulley? maybe it is turning too slow in stop and go traffic

[Formulas]

Who put the timing cover together and on ? There are replaceable sleeves and rubber seals that are easy for a novice or non Pontiac builder to miss installation of

I would research that and plate clearance along with impeller build along with a small hole in a new thermostat to guarantee no air trapping


.

[chuckies76ta]

I have 2 engines like this.
Like guys said cast iron impeller. and check that new rubber sleeves in timing cover.
I run Torker 2 intake on both. Dynoed at 600hp, 600 torque. 10.5 to 1 comp. 950 quickfuel. 12.5 to 12.9 AFR WOT.
I run a 160 thermostat in both engines. Napa Stainless one.
I ran lines off the back of both heads, tied them together then to the heater core.
I run synthetic oil also.
I also run the smaller pulley on the water pump.
Timing is at 32 deg with KRE heads.
My car stays at 160 no matter what. 4 core rad. 76 T/A... My wife's will run 160, occasionally run 170. 68 Firebird.

[HWYSTR455]

You say the timing is not retarded, but what is it? Idle, total, and at cruise?

Is sounding like the temp sensor/controller, if its not coming on until 220, that's part of the problem. But just to say, there's a combo of factors that can present itself as a cooling issue.

.

[Bandit400]

What is your thermostat temp? (Edit: disregard, just saw it in original post)

[andrewT]

Originally Posted by Formulajones

The one we used in the engine are just the simple pipe thread temp senders that are all over ebay, and cost ~$20 We actually bought 3 of them with different temp ratings to experiment with. Just pick one with a fan on/off rating your happy with. They aren't exact and seem to vary 5 degrees or so but not a big deal.

For what it's worth, they came from different suppliers, one is a different name brand, but they all look identical holding them in your hand. So I suspect they are made at the same place.

do you have water flow from the back of your heads? as in having a crossover of some sort? will that help with my flow and in turn lower my temps (along with the other suggestions)

Originally Posted by chrisp

Could be , when the T-stat is open are you seeing a good flow through the rad when cap is off ?

yes sir

Originally Posted by JSPONT

I dropped 15 degrees no other change when I clearance the pump

going to pull pump apart and check this. I hope thats all I need to do!

Originally Posted by steve25

What do the plugs look like?

I don't care about the stateded 11 to 1 the motor has, what is the cranking compression checking in at?

Has TDC been doubled checked?

What Carb is on the motor, and had this been run before on a motor close to this ones Cid and a motor that was Camed close?

carb is a 1000hp was run on a 383 chevy before so no to that. Plugs are fine. Cranking compression was taken last season and was good, just can't remember value right now. TDC has been triple checked

Originally Posted by adynes

I've noticed that my factory gage isn't very accurate compared to the reading from my efi computer.

Also, in your third picture, is that your sensor mounted in the top of the passenger side ("cold side") tank of the radiator? If so, I think you need to mount it on the other side, the hot side of the radiator (or on the engine itself). Aside from being the wrong side of the radiator temperature-wise, the sensor located there might not even be submerged in coolant, as the coolant level gets pulled down significantly on the suction side. My coolant sensor for the efi (that controls the electric fans) is in the crossover.

no the sensor for my fans is on the rad itself but I will be moving to the intake.
That sensor you see on the intake is for my water temp gauge.
Am going to try another gauge (currently using an auto meter pro comp) and I am sure the gauge is fine as I can feel the car behaving differently when its hot but will try another gauge to make sure.

dumb question but can I get smaller water pump pulleys for a pontiac from a regular parts supplier? any part numbers I need to be looking for?